A portable target-triggered fluorogenic RNA switch functionalized hydrogel kit for rapid visual detection of miRNA-126 in colorectal cancer

Developing effective strategies for the sensitive and accurate detection of colorectal cancer biomarkers is of great significance for improving its early screening. Herein, a novel visual detection platform based on target-driven fluorogenic RNA switch lighting-up for label free measurement of miRNA-126 is demonstrated. For the first time, Pepper RNA with an acrydite group (acrydite-Pepper) is covalently immobilized into the hydrogel network via photopolymerization. The fluorogenic RNA switch simultaneously serves as both a capture probe and a signal output probe, and the conformational change of the switch is induced in the presence of target miRNA through Watson-Crick base complementary pairing. This Pepper RNA functionalized hydrogel kit exhibits a limit of detection (LOD) of 23.8 pM and 0.53 pM for the different detection platform of fluorescence microscopic and microplate reader, making it suitable for rapid and sensitive on-site detection. This strategy provides a simple-to-operate, low-cost, and easily visualized new method for the detection of colorectal cancer-related miRNA, laying a foundation for future applications in diluted biological sample analysis and preliminary point-of-care testing (POCT).